A communication system which enables communication link establishment between two Second Generation Cordless Telephones (CT-2) having pagers is the Glenayre MODULAR VOICE PROCESSING.TM. system (MVP.TM.) manufactured by Glenayre Technologies, Inc. A calling party dials an MVP access number and the MVP responds by sending a prompt requesting the caller to enter the phone number and record their name. The caller is put on hold and may continue to hold or leave a message. The subscriber is notified of the call waiting and dials an MVP access number and enters a password. The MVP announces the call and the routing options available to the subscriber. The subscriber can choose to connect the call, continue to hold the call, or transfer the call.
A CT-2 Telepoint system using the MVP system is shown in FIG. 1. A call between a first handset having a pager 102, which will be referred to as the calling party, and a second handset with pager 104, which will be referred to as the subscriber, are processed through the MVP system 112. Calling party 102 establishes a communication link with a first base station 106 and dials in an access number. This access number will route the calling party 102 through the Public System Telephone Network (PSTN) 110 to the MVP system 112. Calling party 102 then enters the phone number for the handset 104 in response to a prompt sent by the MVP 112. The MVP system assigns a telephone line number based on the line the call came in on and looks up the pager number associated with the phone number that was entered. The MVP system 112 generates a page and sends the assigned telephone line number reserved for connection to the subscriber 104 using a paging terminal 116. The paging terminal 116 pages the second handset 104 with the assigned telephone line number while the calling party 102 is placed on hold for a predetermined time during the interconnect process. If the predetermined time elapses without interconnect, the MVP system 112 indicates to the calling party 102 that the subscriber 104 is not available and to leave a voice message, or try to call again later.
The subscriber 104, upon receipt of the page, also has a predetermined time period to respond to the page and be connected. The subscriber's page indicates a call is holding. By entering an MVP access code and choosing to connect the call, the subscriber 104 is linked to a second base station 108, which calls back the assigned telephone line number. The call connection is made from the second base station 108 through an interconnect to the PSTN 110 and from the PSTN through an interconnect to the MVP 112. The MVP system 112 then interconnects the returned subscriber call to the holding calling party 102 through the first base station 106.
There are several disadvantages to the MVP system. A system operator assigns the subscriber a personal telephone number for the MVP system service and a second number for stand-alone paging service. This requires the calling party 102 to remember two numbers depending on which service is desired, two-way calling or paging. A system that would allow the calling party to use one number would be easier to use.
When the call is connected, the call is routed from handset 102 to the base station 106, through the PSTN 110 to the MVP system 112, then back through the PSTN and second base station 108, to subscriber 104. This requires four hardwire interconnects in order to establish the communication link between the first and second handsets. The first interconnect goes from the base station 106 to the PSTN 110, the second interconnect from the PSTN to the MVP system 112, the third from the second base station 108 to the PSTN and the fourth from the PSTN to the MVP system.
Another disadvantage to the MVP system 112 is the additional external hardware needed for connection between the MVP and the paging terminal 116. A system that would not require additional peripheral equipment would make installation of the system less expensive and easier to set up.
System capacity to support the number of subscribers is limited to the number of available ports in the MVP system 112. The MVP 112 is a modular design, therefore expansion requires the addition of trunk cards to increase system ports and overall system capacity.
Call holding is a programmable feature that must be used with caution due to its impact on system capacity. Excessive call holding time by the calling party 102, as experienced in the MVP system, substantially reduces system capacity since that line is reserved until it is released.
Hence, there is a need for a system that would provide two-way calling that would alleviate the problems of installation and cost associated with providing new hardware. An improved system with regards to system expansion and capacity would also be a benefit to the system manufacturer.